This might be one of those paper caps nurses sometimes wear, seen from the underside. (The doctors get to wear more colorful and less stupid looking ones.) Or it might be icing on a cupcake. I’m more inclined to go with that one at the moment, as I’m hungry. Going back to the medical profession, it could be a cross section of a bone. Or the intestines.
Ack, maybe I’m not hungry after all.?